Suzaku data reduction is primarily performed using the HEAsoft package, which is described in detail at: http://heasarc.gsfc.nasa.gov/docs/software/lheasoft/.
HEAsoft is a multimission collection of programs and scripts (frequently also called FTOOLS, for historical reasons), all using a similar interface which can be used both interactively and in scripts. All mission-specific software required to calibrate and analyze Suzaku data are written by the instrument teams and released as a part of HEAsoft and are collectively called the ``Suzaku FTOOLS''. By using the Suzaku FTOOLS Suzaku users can recalibrate their data when new calibration information is made available. HEAsoft is supported on major Unix architectures, such as Linux and OS X. HEAsoft runs on Windows in principle, but not yet as smoothly as on Unix. Therefore, Suzaku users are strongly advised to use one of the supported Unix systems, listed on the HEAsoft website.
Major releases of the entire HEAsoft package are currently
scheduled approximately once a year. As need arises, the Suzaku
FTOOLS may be released as patch releases on a faster
timescale. This guide assumes that the users have installed Suzaku
FTOOLS Version 16 in HEAsoft Version 6.9 or later. An
up-to-date and complete listing of Suzaku FTOOLS can be found
at:
http://heasarc.gsfc.nasa.gov/docs/suzaku/analysis/suzaku_ftools.html.
Since Suzaku data files are in FITS format, other analysis suites (such as CIAO) can be used with Suzaku files to complete certain tasks. However, due to limited resources the Suzaku GOF will focus support on using HEAsoft to analyze Suzaku data and only support other tools as time permits.
Suzaku calibration information is provided to the users via the HEASARC
``Calibration Database'' (CALDB):
http://heasarc.gsfc.nasa.gov/docs/heasarc/caldb/caldb_intro.html.
Many Suzaku FTOOLS cannot run if they cannot access CALDB
files. While it is possible to run the tools by specifying the paths
to individual CALDB files, this is not recommended since it puts undue
burden on the users to know the paths to the correct and up-to-date
calibration files for each calibration parameter of each
tool. Instead, CALDB provides index files and other infrastructure so
that Suzaku FTOOLS can determine the correct file to use, open
it and read its contents. The users of such tools need only specify
``CALDB'' (or ``AUTO'' in some cases; these are the default values in
the Suzaku FTOOLS distributions) instead of the full path name
of calibration files.
As explained at the above URL, CALDB can be installed on the users'
local machines or accessed remotely. The latter ensures that the most
up-to-date version is used, but there may be a penalty in terms of
speed of access. In the former case, it is the local CALDB manager's
responsibility to ensure that the latest version is installed. Note
that the Suzaku calibration files may be updated as frequently as once a
month; the latest version are described at, and can be obtained from
http://heasarc.gsfc.nasa.gov/docs/heasarc/caldb/suzaku/.
To set up access to the local installation of CALDB, source the
caldbinit file in the CALDB tree in the directory software/tools
(either caldbinit.csh or caldbinit.sh can be used depending on the
shell being used; note that these script must be edited to fit the
location of the CALDB on each system). This will set up the
environment variables that are necessary for the use of CALDB. The
remote access method is explained at
http://heasarc.gsfc.nasa.gov/docs/heasarc/caldb/caldb_remote_access.html.
xselect is a multi-mission program which has been widely used
to analyze data from ASCA, ROSAT, BeppoSAX, Einstein, Chandra and other high energy missions. After passing
through standard processing, Suzaku event files do not require any
particular analysis software, since they comply with FITS event file
standards. Nonetheless, the Suzaku GOF recommends xselect as a
convenient and straightforward analysis tool. Therefore, in this
document it is assumed readers will use xselect to extract Suzaku
data into spectra, images, and lightcurves. The primary purpose of
xselect is to provide a ``shell'' that translates simple
commands (such as ``extract image'') into more complicated mission- or
instrument-dependent FTOOLS commands. This guide, however,
will not describe all the features of xselect. Users unfamiliar
with xselect should read the xselect manual, available
at
http://heasarc.gsfc.nasa.gov/docs/software/lheasoft/ftools/xselect/xselect.html.
The most important FTOOL used by xselect, extractor, does the actual work of extracting images, spectra,
light curves or newly filtered event files from input event
files. Users wishing to create scripts based on xselect commands will likely want to use extractor directly.
XANADU is a mission-independent data analysis software package for
high energy astrophysics which is normally distributed as part of the
HEAsoft package. Currently XANADU includes XSPEC for spectral
analysis, XIMAGE for image analysis, and XRONOS for timing analysis.
Suzaku spectral, image, and timing analysis may be carried out within
XANADU. In particular, the Suzaku GOF will fully support spectral
analysis using XSPEC, and provide spectral response files (and/or
response generators) with the XSPEC standard format. This guide
assumes that the user is generally familiar with the XANADU package
but if not, more information can be found at:
http://heasarc.gsfc.nasa.gov/docs/xanadu/xanadu.html.
Profit is a spectral analysis tool with a graphical user interface,
designed generally for high-resolution spectroscopy but with Suzaku in
mind. Profit is in active development and the reader is directed
to
http://heasarc.gsfc.nasa.gov/docs/software/profit/
for downloading instructions and details of its current functionality.
In its initial release, Profit can display Suzaku spectra, focusing in
and out as desired. Emission lines in the spectrum can be labelled
using atomic data from either the ATOMDB or XSTAR line lists. The user
can also select individual emission lines and redisplay the data in
velocity space to search for line broadening or a Doppler shift.
Profit has some ability to fit spectra, although this is rudimentary
compared to XSPEC which is recommended when performing measurements
for publication. Despite this limitation, Profit may be useful as a
``first-look'' tool when examining Suzaku data, especially for users not
familiar with X-ray spectroscopy.